Ceramic ware treating method and apparatus



JUIY 11, 1933 c. L. col-.BERT

CERAMIC WARE TREATING METHOD AND APPARATUS Filed May 24, 1930 's sheets-sheet 1 f lveno: (7a2/rence L. (0M i' Lys.

July 11, 1933. c. L. coLBERT CERAMIC WARE TREATING METHOD AND APPARATUS Filed May 24, 1930 3 Sheets-Sheet 2 Javento): ceL. C026 r Attzys.

Clare July l 1933- c. L. coLBERT 1,917,924

CERAMIC WARE TREATING METHOD AND APPARATUS Filed May 24, 1930 3 Sheets-Sheet 3 ,2 ffy, .5.

721/612 to?. Clarence L. COZ rf.

Patented `luly 11, 1933 f I ori-ICE CLARENCE L. COLBERT, GF ELIZABETH, JERSEY, `ASSIGNOR T FISKE &COMPANY,

INC., OF BOSTON,-i'SSACUSETTS, A COREORATON CF MASSACHUSETTS CERAMIC WARE TEEATING METHOD AND APPARATUS Application filed May 24,

T his invention relates to improved appa-l without manganese oxides, is employed to'v blacken the ware while various other mat-erials may be employed tol'impart various- Htints yto the ceramic ware. Heretofore suoli l2' a surface treatment has vbeen leffected in periodic kilns or the like, `necessitatmg a limitation of output and requiring frequent individual attention to successive batches of 1, articles, as well as involving the likelihood of Y 511 non-uniform treatment of the ware.

rlhe advantages of tunnel kilns are well recognized when a large quantity of bricksor the like are to be manufactured, the warev L I through the kiln;

#being heated, vburned and-cooled in succes- LL sive Zones which are maintained at substantially uniform temperatures,lthe ware being passed through the same upon suitable conveyor means such as successive cars. Such a kiln is controllable to permit uniform treatment of the ceramic material and to avoid the necessity for careful individual attention to the ware passing through various stages.

The present invention is particularly ad- Vvantageous in permitting the surface treatment under heat, or flashing, of ware as it leaves the combustion Zone, of a tunnel kiln, thus making the flashing treatment a part of the cycle through which the bricks pass in the burning kiln. In accordance with this invention. a flashing Zone may be provided in the kiln adjoining the burning zone, suitable sources of coating material being disposed at this portion of tlie tunnel, such for example as furnaces, or nozzles foi-oil, tar or before it passes ,to a gradual cooling zone` wherein the temperature of the ware is.

the like. Subsequent to the flashing zone the 1930. Serial No. 455,291.

gradually lowered before it passes out into the air. This arrangement not only permits the more convenient and economical flashing of brick orother ceramic articles, but also it permits the especially eiiective application of the surface coating agent, since the same may be applied directly to the faces `of the ceramicarticles asv they passr through the yflashing vzone, while all of the ware receives substantially uniform surface'treatment.

Preferably the tunnel is so arranged that the hot gases of the'flashing Zone are pre-j vented from passingout of that Zone into the l cooling Zone, andpreferablya certain portion of tliebases omitted from the' flashing' zone may be returned to the sainey thereby VaffordingV greater' thermal econon'iyfand effectiveness in flashino'.

Referring to the accompanying drawings: Fig. 1 is a broken semi-diagrammatic sectional view of a tunnel kiln embodying the principlesof this invention; l f Fig'. l2 is a corresponding vertical section Fig. 3 is a. transverse section of the flash- 75 ,ing Zone;

Fig. 4 is a view similar to'Fig. 8, but illustrating an optional embodiment of the invention; l l Fig. 5 is a section indicated vby line 5 5 -of Fig. 4;; and

` Fig. 6 is a vertical section of the flashing and annealing Zones. i

Referring to the accompanying drawings, the numeral l designates a tunnel kiln which may be provided with the usual track 2 upon which the cars 3 are disposed, the brick Aor other ceramic articles being supported upon the cars so that their surfaces are exposed for the flashing or coloring treatment. The kiln 90 is provided with a preheating zone adjoining its entrance end, which is designated by theI numeral 6, Het air may be directed tof this portion of the tunnel from a suitable vsource of supply. The air supplied to the 9d preheating zone by duct 8 may, in part at least, be received from the hollow crowns 9 and`19 which are disposed over the combustion and cooling Zonesl respectively of thev tunneh'and are connectedby a. by-pass 20 00 positesides ot' the tunnel in staoce preheating zone, the ware pas-se over the flashing zone. Chambers 118 may be disposed at each side oi the preheating zone and may receive hot air from duct S; openings between these chambers and the interior ot' the tunnel permit the circulation of or combustion zone .vhich is suitable number ot heating i'urnaces 12, which may he hightemperature.

Thus, as shown in Fig. 4, furnaces 14 may be disposer at'each sido ot' the tuunelhaving tire boxes 17to receive the various flashing- 1nediums,suchas coal, zinc oxide; salt and the if' like. The lire-boxes are provided withoutlet .passages ladjoining theloter oi the side wallsofA the tunnel, ie., adjoining the bottom of the ware carried by the cars 3. ii plurality of outlets 2l are provided in the ceiling ofthe tunnel to permit gases from the lire boxes to pass upwardly into a hollow crown for exhaustion or for recirculation.

A plurality of passages 27 connect the crown 25 with the sidesr of the flashingv zone 'so that thegdashing gases may ber recirculated,

while a damper controlled outlet 29 permits the exhaustion of a part of thogases to any suitable point of use. lt is thusevident that circulation ot' the hashing gases or material is induced so that the same inipinges upon the surface of substantially all oi' the ceramic were and so that the latter may be substantially unitormly treated The flashing zone may be oi2 comparatively short extent. and may only have two furnaces, nozzles or the like, one of the same upon each side.

Directly adjoining'thc ilashing zone is a tempering or annealing zone having a plu'- rality of inlet passages preferably damper-controlled adjoiningl the lower part of the'tunnel, whereby a limited quantity oi cool air may pass over the ware, thus abruptly reducing its temperature to a point which is distinctly lower than that of the combustion and flashing zones, but which is materially above the temperature ol the het ware as it leaves the tunnel. y In otherwords, thisrapid .L

cooling of the ware is sulicientto eausethe setting of the.lashingmaterial or surface coating' upon the ware, but does not 'lower `the temperature of the latter sufi cieutly to result in danger of cracking or the lilie.- 1'

' Adjoining the annealing zon-o isjthe cooling zone which may bev conventiona'land which is eilective in permitting the gradual reduction in temperature of the brick from that which it possesses leaving the annealing zone to a temperature which` is not substantially higher than atmospheric temperature.

lWhen certain types of materials are to be employed tor flashing such as oil or tar liquid nozzles may be employed rather than the lire boxes 1T. Such anoptional arrangement is shown in l" 5l wherein nozzles 50 extend into the flashing zone at each side oi the tunnel and a third nozzle 51 may extend into the upper part of the same. Each of these nozzles may be provided with a water-cooling aclret 52 which is connected to inlet and outlet d ucts V53 and 54@ respectively. rllhe fluid such as oil entering the tunnel passes into the preheating zone 6. The hollow crown llover the cooling j vzone receives an' trom any suitable source,

for example, being supplied by the fan 40. A

portion of this airis ted into the cooling zone l jand the lay-pass 9,() over the4 hashing zone to the crown il; thus the air which is heated in the crown 19 passes to the region of the comhustion zone, passing from the crown 9 through the duct El to the preheatin r zone, where a portion otthe warm. air is directly supplied tothe upper part ot' the tunnel and the remainder 'thereof may pass into'chamber 118 at each side of the prehcating zone.v Suit-` able-openingspermitthe air to 'flow from the chambers 118 into'this part of the tunnel and also permit circulation ot moisture-linien air through the chambers, 118 to the outlet pas-. vsages 60. Accordingly the brick or other ware is heated as it passes through the preheating zone to the combustion zone where the furnaces 12 areeflective in burning the brick.

The latter reaches substantially its maximum temperature as 1t enters the flashing zone where the fire boxes 17 are eiilective in flashing the brick. The openings Q11 in the upper part of the flashing zone permit these gases to be exhausted, a portion 'of the same being recu'- culated tlnough passages 2'? in the sidewalls ,Y or the zoneand thus being returned to the interior ot thetunnel. Y The outlet duct 29 is provided with a damper which permits thev exhaustion .of a controllable portion of the gases from the i'lashing vzone to anyy suitable pointot use. Fromv the flashing zone the ware passes to the :mnealingV zone Where coal air entering through the small inlets 83, which through the damper controlled duct 41. thus .95

CII

may 'be damper controlled, is effectiveV in sharply reducing the temperature of the ware so that it passes'V into the cooling zone with a temperature several hundred degrees lower than that which it had when leaving the combustion Zone, although this temperature is sufliciently high to prevent cracking;V In the cooling Zone the gradual reduction in the teinperature of the ware occurs in the usual inanner, the heat thus dissipated being effective in heating the air in crown 19. As shown, suitable air passages may beV provided for cooling the running geais of the'cars.

I claim: Y

l. A tunnel kiln comprising a preheating Zone, acoinbustion zone, heating factors associated with the combustion Zone, a flashing zone adjoining the combustion Zone provided with means forsupplyiug coating material to the hot ware, a tempering Zone adjoining the flashing zone and means for admitting a large volume of cool air directly to the tempering" zone rapidly to reduce the temperature of theY ware therein to a point suflicient to set the finish imparted to the ware bythe flashing treatment, and a cooling Zone adjoiningfthe tempering Zone with cooling means associated therewith to effect the gradual reduction of the temperature of the ware.

2. The method of treating ceramic ware which comprises moving the ware through successive zones which are maintained at substantially uniform temperatures, first moving the ware through the preheating Zone wherein its temperature is gradually raised, then passing the ware through a firing'zoiie where it is subjected to a burning temperature, thereupon passing the ware through a flashing Zone wherein it is subjected to siii'- face treatment at high temperature, then Apasing the ware through an annealing zone wherein the initial cooling of the brick to a predetermined temperature condition is rapidlyeffected to set the finish imparted by the flashing treatment, and thereafter passing the ware into a Zone wherein its teinperature is gradually lower. Y

In a tunnel kiln having a preheating zone. a firing Zone and acooling zone, a flashing zone and a tempering Zone disposed between the firing zone and the cooling none, said tempering Zone having means for rapidly reducing the temperature of the ware emerging fromv the flashing Zone to a point sufilcient to set the finish imparted thereto by the flashingT treatment. Y

Ll. ln a tunnel kiln having` a preheatiiig sono. a firing Zone and a cooling Zone, a flashing Zone and a tempering zone disposed hetween the combustion zone and the cooling zone, said flashing zone being provided with inlets to supply surface coating material at high temperature, and outlets arranged to cooperate with the inlets in causing the circulation of the coating material in Contact with the surface of the ware, `and meansfto zone, said flashing zone being provided with inlets to supply surface coating material at high temperature, and outlets arranged to cooperate with vthe inlets in causing the circulation of the coating material in contact with the surface of the ware, means receiving gases from theoutlets of the flashing zone and supplying a portion of thogases for recirculation through said Zone, and an exhaust duct for a portion ofthe remainder of said gases.

'n G. In a tunnel kilnya flashing Zone adjoin?" ing the combustion zone, means for supplying surface coating at high temperature to the flashing zone includingv inlet passages at either side of the lower portion of the tunnel and a plurality of outlet passages in the. ceiling of the tunnel, and a hollow dome communicating with. rsaid outlet"` passages and a hollow dome communicating with said outlet passages. and receiving the gases of the flashing zone therefrom.

7. A tunnel kilnlcoinprising a' preheating zone, a combustion zone, a flashing Zone7 a tempering Zone, and a cooling zone, means for supplying hot surface coating material to the ware in the flashing Zone, and means for admitting a largeA volume of cool air directly into said tempering zone to ieect the rapid cooling of the ware therein to a point `sufficient to set the finish impart/ed thereto by the flashing treatment, and means arranged substantially toprevent longitinal movement of the gases from the flashing Zone tothe tempering Zone.

8. In a tunnel kiln comprising a preheat- Aing Zone, a combustion Zone, and a cooling'A Zone, a flashing Zone yand an annealing zone between the combustion zone and the cooling zone, a hollow crown over the flashing zone, means supplying surface coating material to the flashing Zone, an outlet to supply gases from said Zone to the hollow crown, and return passages between the crown and the flashing zone to permit recirculation of said gases. Y p

' 9. VIn a tunnel kiln comprising a preheating zone, a combustion Zone, and a cooling zone, a flashing Zone and an. annealing zone between the combustion zone and the cooling lzone, a hollow crown over the flashing Zone7V inlets for supplying hot surface'coating material at opposite sides of the flashing Zone,

outlets to emit gases from the flashing zone to the crown, and passages in the side wallsA soA llO

of the tunnel to supply gases from said crown Y to the sides of the flashingzone for recirculation. Y Y Y l0. In a tunnel kiln comprising a preheating Zone, a combustion zone, and a cooling Zone, a 'flashing zone and an annealing Zone between thevcombustion Zone and the cooling zone, a hollow crown over the hashing Zone, means supplying surface coating material to the flashing Zone, an outlet to supply gasesv from said Zone to the .hollow crown, return passages between the crown andthe -flashing zone to permit recirculation ofgases, and an exhaust` ductconnected to said lcrown and arranged to receive a portion ofthe gases l supplied to the same, whereby a part ot' the gases is recirculated through the hashing zone and a part is exhausted. l

ll. ln a tunnel kiln comprising a preheating Zone, a combustion Zone, and a cooling Zone, a llashing Zoneand an annealing zone between Ythe combustion Zone andthe cooling Zone, a hollow crown over the flashing zone, i

a chamber over the combustion zone, a cham- `ber over the cooling Zone, and a duct for supplying air from said chambers to the region of the preheating zone, means supplying surface coating material to the flashing Zone, an outlet to supply gases from said zone to the hollow crown, andreturn passages between the crown and the flashing zone to permit recirculation of said gases. Y c

12; A tunnel -kiln comprising a preheating zone, a combustion Zone,aitlashing Zone hav- In a tunnel liln having a flashing zone tor imparting a surface iinish to ceramicy ware and a cooling Zone, a tempering Zone intermediate the flashing zone and the Acooling Zone, said tempering Zone having means'for `rapidly cooling the ware emerging from the flashing Zone to a point suflicient to prevent oxidation ol' the finish imparted thereto in the flashing zone.

lll. Method of continuous manufacture of ceramic ware which comprises the successive steps of, first, subjecting the ware toaJ preheating treatment whereby its temperature 'is gradually incr ased, second, subJecting the ware to a burning treatment in an oXldiz'mg atmosphere, third, subjecting the lWare to a flashing treatment in a reducing atmosphere to impart a surtace-linish thereto, fourth, immediately subjecting the ware to a tempering treatmentrapidly to reduce its temperature to set the lim' sh imparted thereto by the ila-shing treatment, and finally, gradually reducing the temperature of the Ware.

Signed by me at Boston, Massachusetts, this 22nd day of May, 1930. 

